This title appears in the Scientific Report :
2021
Please use the identifier:
http://dx.doi.org/10.1021/acsami.1c06771 in citations.
Please use the identifier: http://hdl.handle.net/2128/28148 in citations.
Ultrathin 2D Fe-Nanosheets Stabilized by 2D Mesoporous Silica: Synthesis and Application in Ammonia Synthesis
Ultrathin 2D Fe-Nanosheets Stabilized by 2D Mesoporous Silica: Synthesis and Application in Ammonia Synthesis
Developing high-performance Fe-based ammonia catalysts through simple and cost-efficient methods has received an increased level of attention. Herein, we report for the first time, the synthesis of two-dimensional (2D) FeOOH nanoflakes encapsulated by mesoporous SiO2 (mSiO2) via a simple solution-ba...
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Personal Name(s): | Hua, Fan |
---|---|
Folke, Jan Markus / Liu, Zigeng / Girgsdies, Frank / Imlau, Robert / Ruland, Holger / Heumann, Saskia / Granwehr, Josef / Eichel, Rüdiger-A. / Schlögl, Robert / Huang, Xing (Corresponding author) / Frei, Elias (Corresponding author) | |
Contributing Institute: |
Grundlagen der Elektrochemie; IEK-9 |
Published in: | ACS applied materials & interfaces, 13 (2021) 25, S. 30187 - 30197 |
Imprint: |
Washington, DC
Soc.
2021
|
DOI: |
10.1021/acsami.1c06771 |
Document Type: |
Journal Article |
Research Program: |
Batteries in Application |
Link: |
Published on 2021-06-15. Available in OpenAccess from 2022-06-15. Restricted Published on 2021-06-15. Available in OpenAccess from 2022-06-15. |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/28148 in citations.
Developing high-performance Fe-based ammonia catalysts through simple and cost-efficient methods has received an increased level of attention. Herein, we report for the first time, the synthesis of two-dimensional (2D) FeOOH nanoflakes encapsulated by mesoporous SiO2 (mSiO2) via a simple solution-based method for ammonia synthesis. Due to the sticking of the mSiO2 coating layers and the limited spaces in between, the Fe after reduction retains the 2D morphology, showing high resistance against the sintering in the harsh Haber–Bosch process. Compared to supported Fe particles dispersed on mSiO2 spheres, the coated catalyst shows a significantly improved catalytic activity by 50% at 425 °C. Thermal desorption spectroscopy (TDS) reveals the existence of a higher density of reactive sites for N2 activation in the 2D Fe catalyst, which is possibly coupled to a larger density of surface defect sites (kinks, steps, point defects) that are generally considered as active centers in ammonia synthesis. Besides the structural impact of the coating on the 2D Fe, the electronic one is elucidated by partially substituting Si with Al in the coating, confirmed by 29Si and 27Al magic-angle spinning nuclear magnetic resonance (MAS NMR). An increased apparent activation energy (Ea) of the Al-containing catalyst evidences an influence on the nature of the active site. The herein-developed stable 2D Fe nanostructures can serve as an example of a 2D material applied in catalysis, offering the chance of a rational catalyst design based on a stepwise introduction of various promoters, in the coating and on the metal, maintaining the spatial control of the active centers. |